Short wave wireless signaling



Oct. 22, 1929. A. ESAU 1,732,556

SHORT WAVE WIRELESS SIGNALING Filed NOV. 2. 1926 19f fsqu Patented Get.22, 1929 UNITED STATES ABRAHAM ESA'U, OF JENA, GERMANY SHORT WAVEWIRELESS SIGNALING Application filed November 2, 1926, Serial No.

This invention relates to an arrangement for the generation andtransmission of wire less waves of very short length and is moreparticularly intended to minimize or to practically suppress disturbinginfluences on the reception such as those known as atmospherics andfaclings. According to my in vention I provide means to generate andtransmit two waves of different lengths in simultaneously by onetransmitting arrangement. It has been proved by experiments that anymaterial fluctuations in the receiving intensity due to fading occurringon both waves simultaneously may be regarded as not liable to occur. Bytransmitting, therefore a message simultaneously 'on two different wavesand by employing a suitable receiving apparatus, in the event of thecommunication on one wave breaking down as a result of theafore-mentioned disturbing influences, the

other wave may be relied on to convey the message. According to myinvention I combine for this purpose two transmitting tubes connected ina manner to be hereinafter described which possesses special advantagesover the sending out of a message by two independent transmitters whichlatter presents diliiculties in the simultaneous control of the twotransmitters.

The invention is more fully set forth in the following description,reference being had to the accompanying drawing showing diagrammaticallya preferred embodiment of the invention Two three-electrode vacuum tubesof preferably equal dimensions 1 and 2 having respectively anodes 3 andl, grid electrodes 5 and 6 and incandescent cathodes 7 and 8, have theircorresponding electrodes joined by conducting leads. 10 is a heatingbattery (A-battery) for the cathodes, 9 an anode battery (B-battery) and11 is a high resistance or choke-coil placed symmetrically to both tubesbetween points of the connect ing leads of the grids and cathodesrespect1vely. By this arrangement it is possible to generate very shortelectric waves, the arrangement being similar to the well-knownpush-pull connect-ion already known 1n shortwave work. The oscillatingcircu1t contains merely the inherent grid-anode capacities of 145,738,and in Germany Hovember 10, 1325.

the tubes in series and the inductance of the connecting leads, thusenabling the generation of very short waves down to a few meterswave-length.

A special feature of the invention resides in the use of a variablecapacity 12 interposed asymmetrically both tubes between points of theleads connecting the grids and anodes respectively, thus forming twooscillating circuits 3, 5, 12, and 4:, 6, 12, respectively, havingdifferent natural wave-lengths. Each of both oscillating circuitscontains an inherent grid anode capacity in series with the condenser12, acting thus" as a shortening condenser, and the self-inductance ofthe connecting wires thereof. When employing tubes of differentdimensions the connecting points of the condenser may be varied in orderto obtain the same conditions, it only being always necessary toestablish an electrical asymmetry. Two antenna circuits for radiatingthe oscillating energy may be coupled to the oscillating circuits in anyknown way, e. g, directly to nodes of voltage in the wave carryingmembers of the apparatus as dis closed, for example, by my prior PatentNo. 1775. In the drawing two one-wire an .L, U0 tennee 13 and 14. areshown, directly connected to nodes of voltage a and Z) in theoscillation circuits 3, 5, 12 and 4, 6, 12, respectively. The length ofeach antenna may be one-fourth 0f the wave-length of the oscillationcircuit with which it is connected, or a multiple thereof. A specialadvantage of the arrangement consists in that the energy radiated byboth waves may be simultaneously controlled in accordance with signalsto be transmitted in an easy way, e. g, by inserting a controllingdevice between the leads connecting the grids and cathodes.

What I claim is:

1. An arrangement for short-wave wireless signaling of the characterdescribed comprising in combination two three-electrode vacuum tubeshaving anodes, controlling gridelectrodes and incandescent cathodes,leads connecting each pair of corresponding electrodes, a variablecapacity interposed between points of two of said connecting leads andforming two oscillatory circuits of different natural Wave-lengthscontaining each an inherent inter-electrode capacity in series with saidvariable'capacity and the self-inductance of the connecting loadsthereof, and means to impart the generated oscillations to antennasystems for the simultaneous radiation of signals on two difl'erentwave-lengths.

2. An arrangement for short-wave wireless signaling of the characterdescribed comprising in combination two three-electrode vacuum tubeshaving anodes, grid electrodes and cathodes loads connecting each pairof corresponding electrodes, a variable capacity interposedasymmetrically between points of said connecting leads of the gridelectrodes and anodes and forming thus two oscillatory circuits ofdiflferent natural wave-lengths containing each an inherent grid-anodecapacity in series with said variable capacity and the self-inductanceof the connecting leads thereof, and means to impart the generatedoscillations toantenna systems for the simultaneous radiation of signalson two different wave-lengths.

3. An arrangement for short-wave wireless signaling as set forth inclaim 2 including as high resistance placed symmetrically between pointsof the leads connecting the grid and cathode electrodes.

In testimony whereof I have ailixed my signature.

' ABRAHAM ESAU.

